Suction volume and filtering efficiency of silver carp (Hypophthalmichthys molitrix Val.) and bighead carp (Aristichthys nobilis Rich.)

Abstract

Experiments were conducted to measure the suction volume of silver carp and bighead carp of age I + with respiratory chamber, and to calculate the suction volume and the filtering efficiency with respect to changes in concentrations of food particles.Suction volume (B, ml/mouth) and filtering efficiency (E, %) were calculated using the following formula:where C,,and C,were theconcentrationsofspecific food particlesat the beginningandattheendof experiment, respectively, Vwas thevolume (ml) ofexperimental water, and n was the total number of observation of suction made during the experimental period.The relationships between suction volume (ml/mouth) of age I + silver carp (Bh) and bighead carp (B,) and their standard lengths (L, cm) were: Bh=0.561L -8.94, Bn = 0'627L-7.48, while those of the fingerlings were: Bh =O. l70L -0.837, Ba =O. I57L -0.418.The suction volume of the fingerlings was mainly affected by fish size, the function of temperature between 15 and 25" C being negligible. However, temperature affected filtering rate (filtered volume per unit time) through its effect on filtering frequency. The filtering efficiency of the fishes for rotifers (Brachionus caliciflorus) was 100 per cent. The relationships between filtering efficiency and sizes of food particles smaller than or equal to that of a rotifer were:Eh=25.1 1nE.S.D-13.6, Eu=22.21n E.S.D.-33-1, where Eh and Ea were filtering efficiency of silver carp and bighead carp, respectively, and E.S.D. was the equivalent spherical diameter (pm) of food particles.

Suitability of Lake Erie for bigheaded carps based on bioenergetic models and remote sensing

“…Filtration efficiency of non-motile foods by bigheaded carps is largely controlled by the size of the particle (Dong et al, 1992). Microcystis is colonial and the colony sizes are large enough to be efficiently filtered by bigheaded carps.…”

Isotopic niche overlap of two planktivorous fish in southern China

“…Stable isotopes measure the chemical components assimilated by consumers over time and are hence better indicators of animal feeding and assimilation. Although zooplankton is only a small proportion of the instantaneous gut content, both silver carp and bighead carp have the capacity to filter large amounts of water and may obtain sufficient zooplankton to meet their daily dietary requirements (Dong et al 1992). Recent studies have also shown that both silver carp and bighead carp often have a dramatic impact on zooplankton abundance in lakes and experimental systems (Yang et al 1999;Xie and Yang 2000;Shao et al 2001;Wang et al 2007).…”

The effect of temperature and kairomone on Daphnia escape ability: a simple bioassay

“…The estimated water velocity generated by the pipette strike was 30 cm s -1 , which is within the range of velocities generated by suctionfeeding planktivorous fish (Ferry-Graham et al, 2003). The volume of a single stroke of the pipette was about 2.5 ml, which is roughly equal to, e.g., suction volume of a 15-cm-long silver carp (Dong et al, 2006). To ensure random pipetting, at each transfer the source container was covered with an opaque wrapping, and the pipette tip was placed randomly at different spots in the container at subsequent strokes.…”